Constant velocity universal joints, more particularly VL plunging joints which, in the way as defined above, are axially secured relative to the shaft journal inserted into the inner joint part, were described for the first time in the earlier application U.S. Publication No. 2005/0192106 wherein the rolling boot or the convoluted boot used, in the form of an integral part of the axial securing means, is welded to the inner joint part by means of a new type of axial securing sleeve which preferably consists of plate metal, which is welded to the inner joint part and which is secured with radially elastic fingers with the help of a rolling boot or a tensioning strip in an annular groove of the shaft journal.
It is generally known that sealing assemblies of constant velocity universal joints should comprise a ventilation system which, with an increasing operating temperature, permits a decrease in the excess pressure in the joint interior to prevent the convoluted boot or rolling boot from distending and suffering damage in operation as a result of an unspecified shape. On the other hand, the ventilation system has to be designed in such a way that water and dirt are prevented from entering the joint interior, more particularly when the vehicle in which the constant velocity universal joint is used drives in a wading style. As the percentage of off-highway vehicles increases in all markets all over the world, this has become an increasingly important factor. Ventilation systems which include the deformation of the rolling boot or convoluted boot under the influence of centrifugal forces for controlled releasing or closing purposes are already known.